Professional learning communities (PLCs) have been promoted as a way to provide teachers with greater agency and efficacy in making improvements to their practice, but these expectations often occur in organizational and policy environments that explicitly or implicitly promote expectations of compliance with reforms that others are leading and developing. This chapter argues that, if PLCs are to realize their potential in reform efforts, they need to be explicitly and deliberately constructed in ways that promote teacher agency in leading reform rather than being used as a vehicle to ensure teachers enact mandated or imposed policy or organizational directives. Conceptualizations of teacher professionalism that focused on teachers mastering particular routines and getting practice right have a 40-50 year history. Scanning is a broad look at what is happening for learners that includes both the academic curriculum and personal competencies. PLCs were originally designed to develop greater teacher agency and efficacy by promoting collegial learning through collaboration.